WI: Indigenous Californian civilization?

From what I've read plants were cared for in the Pacific Northwest with changes made to support them and defined plots owned. To me it seems like they were already doing agriculture.
What else do they need to do to make the jump, and how can they?

To me it seems like the wapato could have the selective breeding that tends to make plants better for humans as in increased yields, to make it a staple crop, even if it has to be supplemented with other plants. But was it already at its maximum potential for human use? I somehow don't think that. Which suggests that even more intensive management is needed.
 
But Drake's crew wouldn't bring disease, since I don't think they did OTL. Unless Drake returns and wants to be a conquistador, of course. Since Californian cultures will probably be as rich in gold as the Andes (and could be getting silver from Nevada), that paints a giant target on their back.

They will think of the peoples in the Pacific Northwest as nothing short of violent barbarians, thanks to their widespread practice of slavery and the experience of people like the Haida slave raiding the coasts. Human sacrifice seems likely to get involved somewhere, probably the Norse style of sacrificing slaves.

I was doing a bit from my own TL on the subject of Agricultural Civilization in Oregon


https://www.alternatehistory.com/forum/threads/land-of-salmon-and-totems-2-0.202767/
 
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